Evaluation of Performance Characteristics of a Surface Texturized Metallic Seal Using Helium Mass Spectrometry and Numerical Simulation

Abstract To evaluate the performance of the textured finish, three prototype seal designs were tested with a focus on load and leak rate characteristics. Each seal design had a similar surface finish with differently designed load-response. The goal of the present work was to characterize the initial textured surface concept. This texturized seal could offer a viable metallic alternative to traditional high-load elastomeric seals made of perfluoro-elastomeric compounds and other per/poly fluoroalkyl (PFA)-based options. Due to recent bans and supply chain disruption, alternatives to these materials are needed. The three prototypes were subject to compression and helium mass spectrometry. Seal designs 1 and 2 demonstrated inconsistent performance; seal 3 exhibited a high degree of repeatability with leak rates in the 10−13 Pa·m3/s range. To guide future iterations, the work was compared with a three-stage performance numerical simulation. The first phase modeled mechanical performance at a seal cross section which investigated load compression curves and deformation characteristics using finite element analysis (FEA). The second phase evaluated the surface interactions at variable contact pressures using hardening models and surface field analysis. The third phase evaluated a leak rate model for texturized and nontexturized seal designs using mass flow modeling. Physical test data were compared to simulation predictions in the first and third phases. Simulations had agreeable results with physical testing; however, additional work is needed to refine both physical and simulated efforts.